The comparative study of quartz dust and bleomycin-induced pulmonary fibrosis in rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To compare the pulmonary alveolitis and the early fibrosis of pulmonary fibrosis induced by quartz dust and bleomycin in rats, and investigate their mechanism.</p><p><b>METHODS</b>The female rats were divided into three groups: control group exposed to normal saline by the trachea; SiO2 group exposed to SiO2 by the trachea; BLM group exposed to BLM A5 by the trachea. Each half of the animals were sacrificed on the 7th and 14th day after exposure. The lungs of rats were collected to observe pulmonary alveolitis by HE staining and to observe fibrosis by saturated picric acid sirius red staining. The expression of tumor necrosis factor-alpha (TNF-alpha) and CD68 in pulmonary tissues were analyzed quantitatively by immunohistochemistry and image analysis system.</p><p><b>RESULTS</b>(1) The alveolitis and pulmonary fibrosis of rats in both SiO2 group and BLM group were became more serious gradually over time, HE staining under light microscope showed that BLM group on the 7th day had the most obvious alveolitis (2.814 +/- 0.832), the saturated picric acid sirius red staining under polarized light showed that BLM group on the 14th day had the worst pulmonary fibrosis (1284.57 +/- 554.72), which were significantly higher than those (103.69 +/- 18.29 and 111.78 +/- 37.45) in control group and SiO2 group on the 7th day (P < 0.05). (2) The results of immunohistochemistry examination indicated that the expression (17.100 +/- 1.831) of TNF-alpha in the BLM group on the 7th day was significantly higher than those (0.451 +/- 0.441, 7.909 +/- 1.275 and 13.506 +/- 1.454) in control group, SiO2 group on 7th day and BLM group on 14th day (P < 0.05). The expression (22.778 +/- 2.512) of TNF-alpha in the SiO2 group on the 14th day was significantly higher than those in control group, SiO2 group on 7th day and BLM group on 14th day (P < 0.05). The expression (134.941 +/- 35.951) of CD68 in the SiO2 group on the 14th day was significantly higher than those in control group, SiO2 group on 7th day and BLM group on 14th day (P < 0.05).</p><p><b>CONCLUSION</b>The early alveolitis of BLM-induced lung injury model was more serious than that of SiO2-induced lung injury model, and the fibrosis process of BLM-induced lung injury model was earlier than that of SiO2-induced lung injury model. TNF-alpha plays an important role in the course of both models, but macrophages is involved in SiO2-induced pulmonary in a more continuous way than in BLM-induced pulmonary fibrosis.</p>

Role of DJ-1-induced PTEN down-regulation in migration and invasion of human glioma cells / 癌症

<p><b>BACKGROUND AND OBJECTIVE</b>DJ-1, a suppressor of PTEN, promotes metastasis of different tumors, but its function and mechanisms in glioma metastasis remain unclear. This study aimed to investigate the effect of the DJ-1 protein on the migration and invasion of human glioma cells, and to explore potential mechanisms.</p><p><b>METHODS</b>The eukaryotic expression vector pEGFP/DJ-1 and small interfering RNA (siRNA) were constructed and transfected into human glioma SWO-38 cells. The expression of DJ-1 and PTEN in SWO-38 cells were detected by Western blot. Cell migration and invasion were detected by transwell assay.</p><p><b>RESULTS</b>After transfection of pEGFP/DJ-1, the expression of DJ-1 (1.28 ± 0.15 vs. 0.89 ± 0.04, P < 0.05) and focal adhesion kinase (FAK) phosphorylation (0.76 ± 0.12 vs. 0.51 ± 0.04, P < 0.05) were increased, whereas the expression of PTEN (0.74 ± 0.2 vs. 1.04 ± 0.14, P < 0.05) was suppressed. After transfection of DJ-1 siRNA, both DJ-1 (0.33 ± 0.04 vs. 0.88 ± 0.06, P < 0.05) and p-FAK levels (0.33 ± 0.01 vs. 0.44 ± 0.05, P < 0.05) were decreased, but PTEN expression (1.1 ± 0.06 vs. 0.81 ± 0.12, P < 0.05) was increased. Transwell assay data showed that pEGFP/DJ-1 transfection promoted SWO-38 cell migration (57.2 ± 6.50 vs. 40.4 ± 5.0, P < 0.05) and invasion (54.6 ± 4.9 vs. 27 ± 6.7, P < 0.05), whereas DJ-1 siRNA transfection inhibited SWO-38 cells migration (54.4 ± 6.9 vs. 73.4 ± 7.6, < 0.05) and invasion (44.6 ± 5.8 vs. 69.2 ± 9.2, P < 0.05).</p><p><b>CONCLUSION</b>Over-expression of DJ-1 promotes SWO-38 cell migration and invasion possibly through the DJ-1 and the PTEN/FAK pathway.</p>

Expression of peroxisome proliferator-activated receptor gamma in glioma / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression and significance of peroxisome proliferators-activated receptor gamma (PPAR gamma) in human glioma.</p><p><b>METHODS</b>Immunohistochemical staining for PPAR gamma was performed using biopsy specimens of human glioma of various histological types. Expression of PPAR gamma and GFAP in glioma cell lines SWO-38, U251 and SHG-44 were analyzed using Western blotting and reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>Immunohistochemical study showed that PPAR gamma was expressed in glioma tissues with positive rate of 37.5%. Western blotting and RT-PCR showed that PPAR gamma was expressed in both glioma cell lines SWO-38 and U251, but not in SHG-44 cells. However, high expression of GFAP was detected in SHG-44 cells.</p><p><b>CONCLUSION</b>PPAR gamma is associated with carcinogens of glioma. Actived PPAR gamma by agonist may be a novel approach to the treatment of glioma.</p>

Effects of PTEN gene on human malignant glioma growth in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the biological effects of PTEN gene on the malignant glioma cell line SHG-44. Firstly, A recombinant eukaryotic expression plasmid containing PTEN gene fused with EGFP (enhanced green fluorescence protein) gene was constructed. Secondly, the expression of the recombinant vector in human glioma cells was detected.</p><p><b>METHODS</b>(1) The human PTEN gene was amplified by RT-PCR and inserted into pEGFP-N1 that was selected by T-A subclone, and the recombinant expression vector was obtained. After the recombinant plasmids were transfected into glioma SHG-44 cells by cation polymex, expression of fusion protein was tested. (2) The stable transfected cells were selected by G418 and amplified. Light microscopy and growth curve were used to measure the effects of PTEN expression on cell morphology and proliferation. Expression of GFAP (glial fibillary acidic protein) was detected immunohistochemically.</p><p><b>RESULTS</b>(1) The positive recombinant was sequenced and demonstrated to have the same sequence as that of PTEN gene in GenBank. It was proved that the eukaryotic expression vector pEGFP-PTEN have been constructed successfully and expressed in SHG-44 cells. (2) The SHG-44 cell growth was changed obviously. The expression of GFAP was increased.</p><p><b>CONCLUSION</b>The construction of PTEN eukaryotic expression vector containing green fluorescence protein gene will lay the basis for carrying out further studies on the function of PTEN gene.</p>

Effects of exogenous human chorionic gonadotropin on nude mice bearing endometrial carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of exogenous human chorionic gonadotropin (hCG) on nude mice bearing transplanted endometrial carcinoma.</p><p><b>METHODS</b>Human endometrial carcinoma xenograft was transplanted in nude mice, and the effects of hCG injection on the tumor growth was evaluated according to tumorigenesis and xenograft weights. The expression of Ki-67 in the tumor was determined by immunohistochemistry, and HE staining was performed for morphological observation and measurement of the necrosis area in the tumor. The effect of hCG on fibrosis in the tumor was evaluated with Masson staining.</p><p><b>RESULTS</b>Compared to normal saline-treated tumor-bearing mice, the mice with hCG treatment showed increased tumor weight. HE staining for tumors in HCG-treatment group visualized tumor cell arrangement in glandular structure with smaller necrosis area, and Masson staining identified thick and compact collagen fibers as compared with the thin and loosely arranged fibers in saline-treated group. No significant difference was found in the Ki-67 expression in the tumors between the two groups.</p><p><b>CONCLUSION</b>Exogenous hCG can promote the differentiation of the endometrial carcinoma cells in vivo.</p>